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Biology subjects

Nunez, N. G.

Publications and source records attributed to Nunez, N. G..

5 recordsLinked to original sources

Altered follicular immunity in secondary lymphoid organs is associated with interferon hyperactivity in Down syndrome

Down syndrome, caused by trisomy 21, is characterized by chronic interferon-associated inflammation and immune dysregulation, yet the contribution of human secondary lymphoid organs to shaping this immune landscape remains unclear. Using multimodal single-cell and spatial profiling of human tonsils, we identify extensive remodeling of immune organization in trisomy 21. CD4 T cells are skewed away from canonical follicular helper (TFH) programs toward inflammatory TFH1-like and cytotoxic helper states enriched for interferon-responsive transcriptional programs. Tonsillar TFH cells exhibit increased interferon-{gamma} and interleukin-21 production, indicating inflammatory skewing toward type 1 helper immunity. These alterations are accompanied by changes in dendritic cell and CD8 T-cell compartments, reduced follicular size, increased extrafollicular TFH1-B-cell proximity and altered B-cell differentiation trajectories. Together, our findings identify trisomy 21 as a unique human context to investigate how chronic interferon-associated inflammation reshapes lymphoid tissue organization and adaptive immune cell fate decisions.

immunology↗

Interleukin-17 signaling influences CD8+ T cell immunity and tumor progression according to the IL-17 receptor subunit expression pattern in cancer cells

The role of IL-17 mediated immune responses in cancer is conflicting as pre-clinical and clinical results show tumor-promoting as wel as tumor-repressing functions. Herein, we used syngeneic tumor models from different tissue origins as a tool to evaluate the role of IL-17 signaling in cancer progression, dissecting the effects in cancer cell growth and tumor immunity. We show that absence of IL-17RA or IL-17A/F expression in the host has contrasting effects in the in vivo growth of different tumor types. We observed that lack of IL-17A/F-IL-17RA signaling in host cells changed the expression pattern of several mediators within the tumor microenvironment in a cancer-type specific manner. Deficiencies in host IL-17RA or IL-17A/F expression resulted in reduced antitumor CD8+ T cell immunity in all cancer models and in tumor-specific changes in several lymphoid cell populations. These findings were associated to particular patterns of expression of cytokines (IL-17A and IL-17F) and receptor subunits (IL-17RA, IL-17RC and IL-17RD) of the IL-17 family in the injected tumor cell lines that, in turn, dictated tumor cell responsiveness to IL-17. We identified IL-17RC as an important determinant of the IL-17-mediated transcriptional response in tumor cells and; consequently, as a predictive biomarker of the overall effect of IL-17 signaling in tumor progression. Our findings contribute to unraveling the molecular mechanisms underlying the divergent activities of IL-17 in cancer and provide rational targets for immunotherapies based on personalized approaches.

immunology↗

Single-cell RNA sequencing unveils intestinal eosinophil development and specialization

Eosinophils are an integral part of the gastrointestinal (GI) immune system that contribute to homeostatic and inflammatory processes. Here, we investigated the existence of functional subsets that carry out specialized tasks in health and disease. We used single-cell transcriptomics and high-dimensional flow cytometry to delineate murine eosinophil subpopulations and their ontogenetic relationship in the steady state and during infection and inflammation. Profiling of eosinophils from bone marrow, blood, spleen and several GI tissues revealed five distinct subsets representing consecutive developmental and maturation stages across organs, each controlled by a specific set of transcription factors. Furthermore, we discovered a highly adapted PD-L1+CD80+ eosinophil subset in the GI tract, characterized by its immune regulatory properties, bactericidal activity upon challenge infection and tissue-protective function during inflammation. Our data provide a framework for the characterization of eosinophil subsets in GI diseases and highlight their crucial contribution to homeostasis, immune regulation and host defense.

immunology↗

Tissue-resident FOLR2+ macrophages associate with tumor-infiltrating CD8+ T cells and with increased survival of breast cancer patients.

Macrophage infiltration is a hallmark of solid cancers and overall macrophage infiltration is correlated with lower patient survival and resistance to therapy. However, tumor-associated macrophages are phenotypically and functionally heterogeneous. Specific tumor-associated macrophage subsets might be endowed with antagonistic role on cancer progression and on the development of anti-tumor immunity. For instance, monocyte-derived TREM2+ tumor-associated macrophages have pro-tumorigenic and immunosuppressive functions. Here, we identify a discrete population of FOLR2+ tumor-associated macrophages positively correlating with patient survival in breast cancer. FOLR2+ macrophages are evolutionarily conserved across species and populate human and murine healthy mammary gland. Moreover, FOLR2+ macrophages co-localize with lymphoid aggregates containing CD8+ T cells in breast cancer and across ten other types of cancers. This study highlights antagonistic roles for tumor-associated macrophage subsets and paves the way for subset-specific therapeutic interventions in macrophages-based cancer therapies.

immunology↗

Conventional NK cells and tissue-resident ILC1s join forces to control liver metastasis

The liver is a major metastatic target organ, and little is known about the role of immunity in controlling hepatic metastases. Here, we discovered that the concerted and non-redundant action of two innate lymphocyte subpopulations, conventional NK cells (cNKs) and tissue-resident type I Innate Lymphoid Cells (trILC1s), is essential for anti-metastatic defense. Using different preclinical models for liver metastasis, we found that trILC1 control metastatic seeding, whereas cNKs restrain outgrowth. The antimetastatic activity of cNKs is regulated in a tumor type-specific fashion. Thereby, individual cancer cell lines orchestrate the emergence of cNK subsets with unique phenotypic and functional traits. Understanding cancer-cell- as well as innate-cell-intrinsic factors will allow the exploitation of hepatic innate cells for development of novel cancer therapies. SignificanceInnate lymphoid cells hold great promise for the treatment of metastases. Development of effective therapies based on these versatile immune cells, however, is hampered by our limited knowledge of their behavior in the metastatic niche. Here, we describe that defense against liver metastasis requires the collaboration between two innate lymphocyte subsets, conventional NK cells (cNKs) and tissue-resident type I innate lymphoid cells (trILC1s). We show that different cancers generate their own particular metastatic niche inducing specific changes in cNKs and trILC1s. Further, we uncover specific cNK subsets that can be manipulated to improve their anti-metastatic potential. Our work contributes to understanding how cancer-specific factors and hepatic innate lymphocytes exert mutual influence and how this can be exploited for therapeutic purposes. HighlightsO_LIcNKs and trILC1s collaborate to control hepatic metastasis C_LIO_LItrILC1s restrict seeding and cNKs control outgrowth of cancer cells in the liver C_LIO_LIIndividual cancer cell lines orchestrate a distinct metastatic niche C_LIO_LIThe metastatic niche dictates the phenotype and function of cNKs C_LI

immunology↗